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101.
We report a long-term follow-up of abduction-extension osteotomy of the first metacarpal, performed for painful trapeziometacarpal osteoarthritis. Of a consecutive series of 50 operations, 41 thumbs (82%) were reviewed at a mean follow-up of 6.8 years. Good or excellent pain relief was achieved in 80%, and 93% considered that surgery had improved hand function, while 82% had normal grip and pinch strength, with restoration of thumb abduction. Metacarpal osteotomy was equally successful in relieving symptoms of those with early (grade 2) and moderate (grade 3) degenerative changes. This simple procedure provides lasting pain relief, corrects adduction contracture and restores grip and pinch strength, giving good results with few complications.  相似文献   
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Muscle activity produces an electrical signal termed the myo-electric signal (MES). The MES is a useful clinical tool, used in diagnostics and rehabilitation. This signal is typically stored in 2 bytes as 12-bit data, sampled at 3 kHz, resulting in a 6 kbyte s-1 storage requirement. Processing MES data requires large bit manipulations and heavy memory storage requirements. Adaptive differential pulse code modulation (ADPCM) is a popular and successful compression technique for speech. Its application to MES would reduce 12-bit data to a 4-bit representation, providing a 3:1 compression. As, in most practical applications, memory is organised in bytes, the realisable compression is 4:1, as pairs of data can be stored in a single byte. The performance of the ADPCM compression technique, using a real-time system at 1 kHz, 2 kHz and 4 kHz sampling rates, is evaluated. The data used include MES from both isometric and dynamic contractions. The percent residual difference (PRD) between an unprocessed and processed MES is used as a performance measure. Errors in computed parameters, such as median frequency and variance, which are used in clinical diagnostics, and waveform features employed in prosthetic control are also used to evaluate the system. The results of the study demonstrate that the ADPCM compression technique is an excellent solution for relieving the data storage requirements of MES both in isometric and dynamic situations.  相似文献   
104.
Acidosis in cattle: a review   总被引:1,自引:0,他引:1  
Acute and chronic acidosis, conditions that follow ingestion of excessive amounts of readily fermented carbohydrate, are prominent production problems for ruminants fed diets rich in concentrate. Often occurring during adaptation to concentrate-rich diets in feedyards, chronic acidosis may continue during the feeding period. With acute acidosis, ruminal acidity and osmolality increase markedly as acids and glucose accumulate; these can damage the ruminal and intestinal wall, decrease blood pH, and cause dehydration that proves fatal. Laminitis, polioencephalomalacia, and liver abscesses often accompany acidosis. Even after animals recover from a bout of acidosis, nutrient absorption may be retarded. With chronic acidosis, feed intake typically is reduced but variable, and performance is depressed, probably due to hypertonicity of digesta. Acidosis control measures include feed additives that inhibit microbial strains that produce lactate, that stimulate activity of lactate-using bacteria or starch-engulfing ruminal protozoa, and that reduce meal size. Inoculation with microbial strains capable of preventing glucose or lactate accumulation or metabolizing lactate at a low pH should help prevent acidosis. Feeding higher amounts of dietary roughage, processing grains less thoroughly, and limiting the quantity of feed should reduce the incidence of acidosis, but these practices often depress performance and economic efficiency. Continued research concerning grain processing, dietary cation-anion balance, narrow-spectrum antibiotics, glucose or lactate utilizing microbes, and feeding management (limit or program feeding) should yield new methods for reducing the incidence of acute and chronic acidosis.  相似文献   
105.
Colo-rectal endometriosis requiring colon resection are reported in 8 patients to illustrated the diagnostic and therapeutic problems encountered in the management of this uncommon localisation. Pericatamenial or catamenial bowel symptoms associated with pelvic genital involvement were encountered in all cases. Clinical examination, barium enema and colonoscopy are essential to guide surgical management looking for multiple localisations. However their diagnostic value is low as endometriosis rarely involves the mucosa. Endosonography appears to be very promising in evaluating the depth of infiltration of the bowel. The treatment of bowel endometriosis is controversial and varies greatly according to the patient's complaints and clinical data. The indications and limits of all treatment modalities including abstention, medical, and surgical treatment are discussed. From the cases reported we conclude that symptomatic bowel endometriosis should be fully excised whenever possible, and the surgical procedure should be adapted to the depth of infiltration. A full thickness excision or bowel resection is mandatory in patients with deep muscularis involvement. These procedures, which are often difficult due to extensive fibrosis and adhesions, may be achieved by laparoscopy in selected patients.  相似文献   
106.
OBJECTIVES: Slow potentials appearing during simple repetitive acral limb movement were investigated. Twenty-six patients suffering from drug resistant partial epilepsies and explored with implanted intracerebral electrodes were examined using two protocols. METHODS: In 18 patients, readiness potential (RP), in 13 patients contingent negative variation (CNV), and in 7 patients both protocols, were tested. The recordings from leads with evident pathological EEG activity were excluded from evaluation. The results concerning the slow potentials preceding the movements in RP and CNV protocols have already been published. RESULTS: The movement-accompanying slow potentials (MASP) were polyphasic or monophasic, started before or during the movement. In the primary motor cortex they followed the pre-movement potentials depending on the protocol: in the RP paradigm they were present only contralateral to the movement, but were bilateral in the CNV protocol. In other areas they either followed the potentials preceding the movement, in some cases with opposite polarity, or they occurred alone. MASP was recorded in motor and supplementary motor, premotor and prefrontal, midtemporal, somatosensory, superior parietal and cingular cortices. The cingular cortex was heavily involved in the self-paced movements but rarely in the cued movements. CONCLUSION: The major involvement of the cingular gyrus contrasted with the absence of slow potentials in temporal limbic structures. MASP is evidently a heterogenic phenomenon. Its genesis could be involved in a spread of information through the relevant structures.  相似文献   
107.
We attempted to determine health and economic outcomes from the perspective of an integrated health system of administering enoxaparin 30 mg twice/day versus heparin 5000 U twice/day for prophylaxis against venous thrombosis after major trauma. A decision-analytic model was developed from best literature evidence, institutional data, and expert opinion. We assumed that 40% of proximal deep vein thromboses (DVTs) and 5% of distal DVTs are diagnosed and confirmed with initial or repeat duplex scanning; 50% of undiagnosed proximal DVTs result in pulmonary embolism; 2% and 1% of undiagnosed proximal DVTs will lead to readmission for DVT and pulmonary embolism, respectively, and pulmonary embolism-related mortality rates range from 8-30%. Length of hospital stay data and 1996 institutional drug use and acquisition cost data were used to estimate the cost of enoxaparin and heparin therapy. Diagnosis and treatment costs for DVT and pulmonary embolism were derived from institutional charge data using cost:charge ratios. A second analysis of patients with lower extremity fractures was completed. One-way and multiway sensitivity analyses were performed. For 1000 mixed trauma patients receiving enoxaparin versus heparin, our model showed that 62.2 (95% CI -113 to -12) DVTs or pulmonary emboli would be avoided, resulting in 67.6 (8 to 130) life-years saved at a net cost increase of $104,764 (-$329,300 to $159,600). Enoxaparin versus heparin resulted in a cost of $1684 (-$3600 to $9800) for each DVT or pulmonary embolus avoided and a discounted cost/life-year saved of $2303 (-$8100 to $19,000). For 1000 patients with lower extremity fractures, enoxaparin versus heparin resulted in a cost of $751 (-$4200 to $3300) for each DVT or pulmonary embolus avoided and a discounted cost/life-year saved of $1017 (-$10,200 to $6300). Although enoxaparin increases overall health care costs, it is associated with a cost/additional life-year saved of only $2300, which is generally lower than the commonly used hurdle rate of $30,000/life-year saved. The cost-effectiveness ratio is more favorable in patients with lower extremity fractures than in the general mixed trauma population.  相似文献   
108.
Under in vitro conditions, muscle larvae of Trichinella spiralis secreted minute amounts of a cysteine proteinase into the outer environment from the stichosome. The proteinase hydrolyzed azocoll at pH 5.0 but not a number of synthetic N-blocked and N-unsubstituted proteinase substrates at this pH. The reducing compound dithioerythritol enhanced the enzyme activity, but the thiol-blocking reagent sodium-p-hydroxymercuribenzoate (0.1 mM) was without effect. Phenylmethylsulfonyl fluoride (PMSF) (2 mM) and leupeptin (100 mM) produced partial and complete inhibition, respectively, whereas soybean trypsin inhibitor, pepstatin A, and 1,10-phenanthroline were non-inhibitory. Calcium (1 mM) produced a slight decrease in the activity that was reversed by 1 mM EGTA. Although multiple proteinase activities were detected histochemically in the somatic muscles, stichosome, midgut, and genital primordium of the muscle larvae, none of these enzymes appeared to be the one secreted. Several histochemically demonstrable proteinases were also found in the cells of 48- to 72-h-old juveniles of the parasite. One was localized in the esophageal lumen and at or around the anterior esophagus of the larvae, where developing stichocytes are believed to occur. The proteinase hydrolyzed N-acetyl-L-methionine-L-naphthyl ester and was sensitive to the metal cation-complexing compound EGTA as well as to PMSF, an inhibitor of serine proteinases.  相似文献   
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110.
A longitudinally linked data set for Georgia was used to identify characteristics, including previous prenatal care use and complications at the first birth, associated with prenatal care use in the second pregnancy among 8,224 African-American women. More than 70% of the women who were < 25 years of age at their first birth (younger women) and almost 40% of women who were > or = 25 years at their first birth received inadequate care with at least one of their first two births. Women who received inadequate care in their first pregnancy were more likely to receive inadequate care in their second pregnancy than women who received adequate care in their first pregnancy. Younger women with a history of a stillbirth, neonatal death, or vacuum extraction were less likely to receive inadequate care in their subsequent pregnancy. Although this study was not able to evaluate the content of prenatal care, it suggested that many African-American women may not receive sufficient care to prevent adverse pregnancy outcomes. Women who receive inadequate care in their first pregnancy must be targeted for interventions that help them overcome economic, situational, or attitudinal barriers to receiving adequate care in their next pregnancy.  相似文献   
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